1. Field of the Invention
The present invention relates to an eccentric seat, especially for an eccentric seat for an automobile grinding machine used for polishing or waxing an outer surface of an automobile.
2. Description of Related Art
An eccentric seat is mounted on a front end of an automobile grinding machine, such that the automobile grinding machine polishes or waxes an outer surface of an automobile with the eccentric seat.
With reference to FIG. 9, the conventional eccentric seat comprises a base 60 and a grinding device 70. The base 60 comprises a base space 61 and two base holes 62. The base space 61 is formed inside the base 60. The base holes 62 are formed in the base 60 at two opposite sides respectively and communicate with the base space 61. The grinding device 70 comprises a bearing 71 and a grinding head 72. The bearing 71 is mounted in the base space 61 and an outer wall of the bearing 71 abuts an inner wall of the base 60. The grinding head 72 is mounted in the bearing 71 and abuts an inner wall of the bearing 71. The grinding head 72 comprises a linking hole 721 formed in an end of the grinding head 72, and the linking hole 721 can align with the base holes 62.
In use, the base 60 is combined with a grinding machine, and the grinding head 72 is connected with a grinding body. Because the end of the grinding head 72 in which the linking hole 721 is defined is free for rotation, to connect the grinding body with the grinding head 72 requires a fixing stick 80. The fixing stick 80 is inserted into the base holes 62 and the linking hole 721 in order to fix the grinding head 72 relative to the base 60, such that the end of the grinding head 72 in which the linking hole 721 is defined is made non-free for rotation, and then the grinding body can be assembled on the grinding head 72 easily. The fixing stick 80 must be removed when the eccentric seat is rotating for polishing or waxing an automobile in order to prevent the fixing stick 80 from being thrown off from the linking hole 721 and the base holes 62. However, the fixing stick 80 must be inserted into the base holes 62 and the linking hole 721 again when the grinding body is to be replaced, and it is inconvenient for use.
On the other hand, when the grinding machine combined with the base 60 is powered on, the base 60 rotates by the grinding machine and drives the grinding head 72 to rotate by the bearing 71. The grinding body connected with the grinding head 72 will be used to polish or wax an outer surface of an automobile. Because the grinding head 72 is driven to rotate only by the bearing 71 and the centrifugal force, a friction between the grinding body and the outer surface of an automobile will slow down a speed of rotation of the grinding head 72. As a result, the conventional eccentric seat is suitable only for waxing an automobile but not for polishing an automobile.